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Cabrillo illustration
DID YOU KNOW?
There are 234 prisms made of hand-ground crystal in the lighthouse’s Fresnel lens, developed by French physicist Augustin-Jean Fresnel. / The third-order Fresnel lens is a relic of the past; the lenses were made in France and what was once Czechoslovakia, but all the craftsmen who knew how to make them were killed in WWII.